Lubrication composition



Patented Sept. 23, 1952 iniim Company of America';

- Pi tt'sburgh; 2a a -corporation of Pennsylvania momma his, inventionrelates it improved; lubricants.

such as'oils, greases,orsemhfluidjoils containing as a major lubricating,compgnentghydro: carbon oil of natural,ror synthetic origin; In".particular, the inventionv r.elates. to.- lubrica ing, compositions ofthis. typ having improved ,exr,

treme pressure characteristics;

Requirements 'uponlubri'cants by, deyelopmenti in mechanicaldesigniareirigid. and; drastic-I In manyinstances pressures at bearing.surfaces a e.

higher than thosewhichpetrolemnmiIsJWiII'I Qrmally withstand;Illustrative ar e,th,e conditions.

encountered inflth'e' lubrication. of automotive hypoid gears, heavilyloaded. milllpin'ion ,lgears,

naval turret gearsand the like. In manylmael i chines operation is, atleastlin'part, under con-V ditions of thin film lubrication, or. undersimilar, conditions where film strength. oilinessandanti-L wearcharacteristics of, high order. are required of the lubricating medium.

The principal object of-this. 'invention is'the provision of a newcomposition .ofnmatter con.-

sisting of a compounded lubricating productposfilm strength, oiliness,andanti-v'vear characteristics.

In accordance with'thi's invention these. ob.-

jects are'achieved in substantial part by provide ing a lubricant, theessential, lubricating come ponents of'which area major amount, of;ahy-v drocarbon lubricatingcomponent which may be,

oil or grease and a minor amount of a :body of boron fluoride-and asubstanceselected;from the class consisting of the fatty-acid esters ofmonohydric alcohols and polyhydric alcohols 'more specifically describedbeloww Theproportion. of this body to the hydrocarbon-component-shouldbe such, however, that-the-mixture, contains at least 0.001% by, weightof-boronrfluoride (BEs).

while, on the other handymore-than 3%idoes not; improve the lubricant.-Withinthis rangeithas been found that the best resultsjare obtained byproviding from 0.1 to'1.0 percent ofboron fluoride,

in the final lubricant'mixture. The choice oijjthe particular body to beemployed anditsboron.flue;

ride content will of course depend onsuchimate ters as cost, ease ofmixin and thenaturleofthe lubrication problem.

' The a principal advantages and effectiveness of.

thisnew compounded lubricant are maintained (Application Decemblenli1949, s erialrlslo. 133,:583.

whem in-a-ddition to theabcve mentioned-essen-= tial components there:are-likewise-present in the lubricating composition other componentsadded to improve some specific characteristicor property thereof; "suchas viscosity; pour-point,

oiliness; flow, anti -wear- -characteristics;- filrn strength or thelike; the effect of" the-definedbo'ron: fluoride-containing:body;whensimilar, be-' ing largely additive: Such diluents or'addit-ions maytherefore,- for the purposes-ofthis invention;- be regarded; as a'non-essentialportion of-the composition,- regardless oftheirspecifickbene fioial or functionaleffeot. The same maybesaidofjsubstances-known as extreme pressure additives, such, as -substancescomposed -;of-;ch lorine,;

sulphur or lead, containing cornponnds or ma teriais; it; beingobservable that the presence of the defined-"boron fluoride-containingbodies: is;' effective toincrease: the :XtIQHl-B" pressure-characteristics ofithe compositionseverr when other-- eXtreme-pressureadditives{are"present'; I

The-- organic- BB3 body, which irr-accoldance with this; inventionisblendedywi-th the hydro;; carbon ;component; :may "be prepared invarious: ways but'is; for the most part;- conveniently {prepared byexposing the fatty acid esterito diregt contact with; gaseousg-BFr. Thiscan;- be easily c ompli h d un e 'ordinaryfatm snhe ic PIG ur yn bb inthe ase us- BFQ: th ou h the. tt cidester n a'li uidi tate ft star s nt: i i a om. m at e" i sh ul the heated o an ma a ned" a a. e er ure slintl above t -meltinene n s le orl fiC-l th ushthe. ra e' flqw of t e asis no lcrit pali with respe ti olformation of t e .35 1 additive, youthe now shq ld'he on rq ledtoavq d:nnduelossg The rate oflac'ceptanc'eof.,the;.. 3E3} by the fatty.

cidesterisrimprbved; e qllid ssti m a th asnisiintroduced The amour:inns. accepted by, the ester, isindicatd by th in 1385iinlweiahtlofitheltreated mass. Thejin'troductiqn ,ot the gas. may,thereforeflbel continued .luntilr, a predetn-L imd"in .reaed..weig ht,.short or saturation,,has, been..obtained,or,the flowofi asmaylie-prolon ed until no further increase in weight is closer e r-et offatty acid ester may have a different saturation making it darker.

point or the desired 33% content may differ for various esters. Thisdoes not detract from the value of the Bib-containing body in improvingthe load bearing quality of a hydrocarbon lubricant.

Other methods of introducing BF3 can be employed, of course. Forexample, the fatty acid ester may be exposed tothe gas at highertemperatures and pressures and thus shorten the time required tointroduce the desired amount of BF3. Naturally, the temperature andpressure should be such that the fatty acid esteris not decomposed toany substantial degree. 'Another method of contacting the ester with El's is to add compounds to the ester which can be decomposed with therelease of BFs. Such compounds the invention do not depend" upon' or"are respon cant and, in many instances, to definitely im- The amount ofthese organic BF: bodies necessarily present prove its anti-wearcharacteristics.

to produce these specific effects is very small.

, The amounts used, should in any case, as menas NH4BF4, BFa-NHs, theheavy metal iiuoboratesor even other organic materials previouslytreated with BFs may be employed. To effect decomposition it is usuallynecessary to heat the mixture of fatty acid ester and the BFs-containingsubstance. Further, it may be desirable to remove any residues resultingfrom the decomposition.

The amount of BF: that can be introduced into different fatty acidesters will vary, as mentioned above, however, from 10 to percent byweight is preferred where the saturation point permits it. In any case,the fatty acid esters should be treated with sufiicient fluoride toprovide the desired BF3 content in the lubricating composition as only aminor proportion of the additive is employed.

The resultant product may, in some instances,

be an actual compound, there being some evi. 3

dence to indicate that such is its nature, or it may be an additive orcoordinate compound or even a, solution or dispersion. I prefer,however, to term the product a body or composition consistingessentially of fatty acid ester and BF: and, therefore not tocharacterize thestate of association of the fluoride and the ester. Inany event, the fatty acid esters act as acceptors of BF:: to produce abody or substance having positive advantages as an additive inlubricating compositions.

The following list of fatty acid esters of monohydric and polyhydricalcohols is illustrative of the class which when treated with BF3produce the bodies just described: esters of normal alkyl monohydricalcohols and monocarboxylic acids such as those of methyl through cetylalcohols with the straight chain fatty acids butyric through stearic;esters of aromatic and cyclic alcohols such as the phenyl, cresyl,resorcinyl, hydroquinyl, furfuryl, benzyl, naphthyl, terpenyl, menthyland bornyl esters of fatty acids; both symmetrical and unsymmetricalesters of polyhydric alcohols such as those of the glycols and glycerylswith fatty acids, including the ethylene, propylene, butylene, andpolyalkylene glycols as well as the polymeric glycols of highermolecular weight and the mono-, di-, and triglyceryl compounds; and suchesters of polyhydric alcohols as the sterols, cellulose, glucose,sucrose, rafiinose,

and sorbitol.

The introduction of the BF: into the fatty acid ester may change thecolor of the ester, 'often Also, the liquid ester may become thicker asthe introduction of BF: proceeds and the melting point of the endproduct may be higher than that of the original ester. Such changes donot affect the advantages gained from the presence of the BFs-containingbodies in a hydrocarbon lubricant, certainly the results of tioned'abovefprovide at least 0.001% by weight of.BF3 in the final mixture.The amount of any given BEE-containing body desirably present to produceoptimum effects in any particular hydrocarbon lubricant can be readilydetermined by simple trial, the optimum usually being found within therange of 0.5 to 5 percent by weight of the fatty acid ester BR. body.Amounts below about 0.01 percent by weight often do not producesufficient effect to' be usually characterized as commercial, but theeffect produced is such as to be useful under exceptional conditions.One may use a relatively small amount of an additive containing asubstantial quantity of BF: or a larger amount of the same or anotheradditive which contains a smaller proportion of BFs to introduce a givenquantity of BFs into the hydrocarbon component. In any event, theorganic BF3 additive forms a minor amount or proportion of thelubricating composition. 7

Theload' bearing qualities of a lubricant may be relatively determinedby various methods. The

method used to obtain the comparative data hereinafter set forth ispracticed on a Falex machir ie and consists in submitting smallquantities of the lubricant to the action of a rotating steel journalrotated in contact with two V shaped bearing blocks. During testingmeasurable pressure was applied to the rotating journal by use of anautomatic loading device. The two bearing blocks and the journal weresubmerged in the lubricant sample throughout the tests. In each and 300pounds at higher pressure; the results are not absolute but arecomparative with a standard run under the same conditions. In the testsby which the results set forth in the following table were secured, thehydrocarbon oil was in all cases the same, being a straight mineral oil.In all cases 1 percent by weight of additive waspresent in the oil. Theadditive had been'prepared .by passing BF3 through the fatty acid esteruntil the weight of the body became substantially constant, that is theester became saturated with the BFz, as has been described hereinabove.Each comparative test was run on two samples, one samplebein the oilcontaining 1 percent by weight of a fatty acid ester, the other samplebeing the oil containing the same weight of a BFz-containing body. Inthe first column of the table the nature of the additive is set forth,in the second column is listed the BFs content of the treated material,in the third column is the BF: content of thellubricant, in the fourthcolumn the failure load in pounds is given and in the fifth column isshown the percentage.

5 increase in failure load caused by the presence of the BFa-containingbody.

6 from 0.001 to 3 per cent by weight of'B-Fs, said lubricatingcomposition possessing extreme pres- Percent Percent Failure Percent-Additive BF: in BF; in Load in age Additive Lubricant Pounds IncreaseButyl laurate l, 000 I Butyl laurate+BFs 23. 0. 23 4, 000 Methyl olcatel 0 I 300 Methyl o1eate+BFa Cyclohexyl steal-ate. 0 I 233 Oyclohexylstearate+B Fa Butyl stearate 0 x 245 Butyl stearate+BFs..... Butylacetyl ricinoleate 131 Butyl acetyl ricinoleate-l-B Glyceryl laurate l245 Glyceryl laurate+BF; Diglycol stearate 50 I 433 Diglycol stearate+BFa Nonaethylene glycol monostearate. l 270 Nonaethylene glycolmonostearate+BFa 45. 0. 45 4, 000

1 Greater than.

The machine on which the tests were run had a capacity of 4500 pounds.Where this capacity was approximated or exceeded the failure load isindicated above as being greater than 4000 pounds. These tabulatedresults are indicative of the improvement obtained by the practice ofthis invention. In general, torque and tempera- --ture values obtainedduring these tests indicated that the organic BFa body improved frictionqualities and observations simultaneously made indicated increases inanti-Wear characteristics.

In compounding lubricant compositions of the type herein described andclaimed the organic BF: additive may merely be mixed with thehydrocarbon lubricants, the properties of which are to be improved.Where the additive is insoluble in the lubricant or it is desired toincorporate therein amounts in excess of solubility, emulsions ordispersions may be prepared according to known principles.

This application is a continuation-in-part of my prior applicationSerial No. 714,909 filed December 7, 1946 now abandoned, and entitledLubrication Composition.

Having thus described my invention and the known advantages thereof, Iclaim:

1. A lubricating composition comprising a major proportion of ahydrocarbon lubricating oil blended with a minor proportion of a bodyconsisting essentially of a substance selected from the class consistingof the fatty acid esters of monohydrlc alcohols and polyhydric alcoholsand BF:;, said fatty acids being those containing from 4 to 18 carbonatoms, said body being prepared by exposing said fatty acid esters todirect contact with a substance selected from the class consistin; ofgaseous BF: and decomposable compounds yielding gaseous BR; and beingpresent in such amount that the lubricating composition contains surecharacteristics superior to those emibited by a similar composition inwhich the minor proportion aforesaid consists of fatty acid ester.

2. A lubricatin composition comprising a major proportion of ahydrocarbon lubricating oil blended with a. minor proportion of a bodyconsisting essentially of a butyl ester of a fatty acid containing from4 to 18 carbon atoms and BFs, said body being prepared by exposing saidbutyl ester to direct contact with a substance selected from the classconsisting of gaseous BE; and decomposable compounds yielding gaseousBF; and being present in such amount that the lubricating compositioncontains from 0.001 to 3 per cent by weight of BFs, said lubricatingcomposition possessing extreme pressure characteristics superior tothose exhibited by a similar composition in which the minor proportionaforesaid consists of butyl ester. 40

EGBERT MASON KIPP.

REFERENCES CITED The following references are of record in the file ofthis patent:

45 UNITED STATES PATENTS OTHER REFERENCES Boron 'Irifluoride and ItsDerivatives," Booth et al., John Wiley 8a Sons, 1949, pp. 72-74.

1. A LUBRICATING COMPOSITION COMPRISING A MAJOR PROPORTION OF A HYDROCARBON LUBRICATING OIL BLENDED WITH A MINOR PROPORTION OF A BODY CONSISTING ESSENTIALLY OF A SUBSTANCE SELECTED FROM THE CLASS CONSISTING OF THE FATTY ACID ESTERS OF MONOHYDRIC ALCOHOLS AND POLYHYDRIC ALCOHOLS AND BF3, SAID FATTY ACIDS BEING THOSE CONTAINING FROM 4 TO 18 CARBON ATOMS, SAID BODY BEING PREPARED BY EXPOSING SAID FATTY ACID ESTERS TO DIRECT CONTACT WITH A SUBSTANCE SELECTED FROM THE CLASS CONSISTING OF GASEOUS BF3 AND DECOMPOSABLE COMPOUNDS YIELDING GASEOUS BF3 AND BEING PRESENT IN SUCH AMOUNT THAT THE LUBRICATING COMPOSITION CONTAINS FROM 0.001 TO 3 PER CENT BY WEIGHT OF BF3, SAID LUBRICATING COMPOSITION POSSESSING EXTREME PRESSURE CHARACTERISTICS SUPERIOR TO THOSE EXHIBITED BY A SIMILAR COMPOSITION IN WHICH THE MINOR PROPORTION AFORESAID CONSISTS OF FATTY ACID ESTER. 